1. Field of the Invention
This invention relates to computer systems, and more particularly, to power management of memory subsystems.
2. Description of the Related Art
During the design of a computer or other processor-based system, many design factors must be considered. A successful design may require several tradeoffs between power consumption, performance, thermal output, and so forth. For example, the design of a computer system with an emphasis on high performance may allow for greater power consumption and thermal output. Conversely, the design of a portable computer system that is sometimes powered by a battery may emphasize reducing power consumption at the expense of some performance.
Various system components may contribute a disproportionate amount to the power consumption of a processor-based system. In particular, those components that make the largest contribution to system performance may also consume the most power. For example, processors may consume more power than other system components, with the power consumption increasing with the number of processor cores included. In computers and other processor-based systems, the contribution of memory to overall power consumption is increasing. For example, in personal computer systems (both desktop and portable systems), the amount of DRAM (dynamic random access memory) has increased with demands for increased system performance. The power consumption of memory thus takes on more significance as a factor in the design of a system. Higher performance for memory-based systems may result in higher power consumption from the system memory. Conversely, limiting power consumption of a system memory may in turn limit system performance.